亚硝胺与泌尿生殖系统癌症关系队列研究的Meta分析

目的 基于研究证据等级较高的队列研究结果，对亚硝胺与泌尿生殖系统恶性肿瘤发生/死亡风险的关系进行系统检索和Meta分析。 方法 通过系统检索《中文期刊全文数据库》、《中国生物医学文献数据库》、《万方电子期刊》、PubMed、EBSCO等文献数据库，纳入N-亚硝胺与全部恶性肿瘤、泌尿生殖系统恶性肿瘤发生/死亡风险队列研究文献，采用Rev Man 5.1软件进行Meta分析。 结果 本研究共检索到13篇亚硝胺与恶性肿瘤关系的队列研究文献，纳入其中含有全部恶性肿瘤和泌尿生殖系统恶性肿瘤的文献7篇进行Meta分析；亚硝胺与全种类恶性肿瘤风险存在显著性关联(RR=1.17，95%CI为1.02～1.34)；与泌尿生殖系统恶性肿瘤发生风险无显著性关联(RR=0.99，95%CI为0.95～1.03)，其中与卵巢癌(RR=0.87，95%CI为0.69～1.08)、乳腺癌(RR=1.03,95%CI为0.94～1.12)和前列腺癌(RR=0.97，95%CI为0.92～1.03)等生殖系统癌症无显著性关联；但是能显著增加泌尿系统膀胱癌的发生风险(RR=1.26，95%CI为1.01～1.57)。 结论 现有人群队列研究证据显示，亚硝胺能显著增加全部恶性肿瘤发生死亡的风险，但是与不同种类泌尿生殖系统恶性肿瘤发生风险的关系存在差异，显著增加膀胱癌风险，而与卵巢癌、乳腺癌和前列腺癌无明显关联。现有相关研究数量较少，仍需积累队列研究证据证实亚硝胺与泌尿生殖系统恶性肿瘤发生/死亡风险的关联性。 

Relationship between N-nitrosodimethylamine and risk of urogenital cancers: a Meta-analysis based on cohort studies

Objective To analyze the relationship between N-nitrosodimethylamine(NDMA) and the risk of urogenital cancers by means of Meta-analysis based on cohort studies. Methods The cohort studies on the carcinogenic NDMA and occurrence/dead risk of malignancy of genitourinary system among population that published in journals from 1980 to 2014 were identified from the following databases:the Chinese Journal Full-text Database(CNKI),Chinese BioMedical Literature Database(CBM),Wanfang Database,PubMed and EBSCO.The fix and random effects model was employed and statistical analysis is conducted using RevMan 5.1 software. Results A total of 13 studies were found,of which 7 articles including urogenital cancers were included in the Meta analysis.There was significant correlation between NDMA and all kinds of cancer(RR=1.17,95%CI 1.02-1.34).The NDMA did not have positive effect with urogenital cancers(RR=0.99,95%CI 0.95-1.03).There was not significant positive correlation between NDMA and prostate cancer(RR=0.97,95%CI 0.92-1.03) and ovarian cancer(RR=0.87,95%CI 0.69-1.08),but NDMA could increase the risk of breast cancer without significance(RR=1.03,95%CI 0.94-1.12).However,the NDMA had positive effect with bladder cancer(RR=1.26,95%CI 1.01-1.57). Conclusion The population cohort studies have showed that the NDMA would not significantly increase the risk of urogenital cancers,but had different effect with different types.It is essential to accumulate evidence derived from population cohort studies to prove the correlation.